1. Technical Field
The present disclosure relates generally to communication systems; and, more particularly, to symbol mapping and/or symbol de-mapping (e.g., modulation and/or demodulation) within various communication devices operative within such communication systems.
2. Description of Related Art
Data communication systems have been under continual development for many years. One such type of communication system that has been of significant interest lately is a communication system that employs iterative error correction codes (ECCs). Communications systems with iterative codes are often able to achieve lower bit error rates (BER) than alternative codes for a given signal to noise ratio (SNR).
An ideal communication system design goal is to achieve Shannon's limit for a communication channel. Shannon's limit may be viewed as being the data rate to be used in a communication channel, having a particular SNR that achieves error free transmission through the communication channel. In other words, the Shannon limit is the theoretical bound for channel capacity for a given modulation and code rate.
Generally speaking, within the context of communication systems, there is a first communication device at one end of a communication channel with an ECC encoder and second communication device at the other end of the communication channel with an ECC decoder. In many instances, one or both of these two communication devices includes both the encoder and decoder (e.g., for bi-directional communications). The transmitter and receiver may use various forms of symbol mapping and/or modulation to generate symbols that carry more than one bit of information (e.g., associated with constellation points of the symbol mapping and/or modulation) to increase throughput of information within such communication systems.